8.5 mm Drill Bits | McMaster-Carr

Extended Length—Drill through panels and thick workpieces with our longest bits. Their length is good for creating deep holes but makes them less rigid than other bits. As a result, they are more prone to wobbling or breaking, especially when drilling hard materials.

Black Oxide—The dark finish increases wear resistance and reduces friction to improve chip flow, so these bits can last 50% longer than uncoated bits.

Titanium Nitride (TiN) Coated—Drill at higher speeds and last longer than uncoated and oxide-coated bits, especially on tough materials like hardened steel and nickel.

Gold Oxide—Like black oxide, this finish adds wear resistance and reduces friction for improved chip flow. Because it’s less prone to flaking off, it offers better rust protection when bits aren't in use.

Uncoated—The most economical option, uncoated bits perform best when used on low-carbon steel and aluminum. Polished to reduce friction, they're also known as bright finish bits.

					Shank				Each		Package
	Drill Bit Size, mm	Decimal Size Equiv.	Overall Lg., mm	Max. Drilling Dp., mm	Type	Size	Drill Bit Point Type	Mfr.		Each	Pkg. Qty.		Pkg.
Jobbers' Length







				Black Oxide

				8.5	0.3346"	117	58	Round	8.5 mm	Standard	Dormer Pramet	2958A133	00000	10	2958A232	000000


				8.5	0.3346"	156	58	Morse Taper	Morse 1	Standard	Dormer Pramet	3070A135	00000	—	———	0




						Titanium Nitride (TiN) Coated

						8.5	0.3346"	117	58	Round	8.5 mm	Standard	Chicago-Latrobe	8950A23	00000	—	———	0




								Gold Oxide

								8.5	0.3346"	121	86.1	Round	8.5 mm	Split	Viking Norseman Drill	30565A311	0000	5	30565A444	00000




										Uncoated

										8.5	0.3346"	121	74.6	Round	8.5 mm	Standard	Viking Norseman Drill	2951A142	0000	—	———	0


										Short Length







														Black Oxide

														8.5	0.3346"	79	20	Round	8.5 mm	Split	Dormer Pramet	28255A55	0000	—	———	0




																Titanium Nitride (TiN) Coated

																8.5	0.3346"	79	38.1	Round	8.5 mm	Split	Dormer Pramet	2979N29	00000	—	———	0


																Extended Length







Black Oxide

8.5	0.3346"																			165	109	Round	8.5 mm	Standard	Dormer Pramet	88455A124	00000	—	———	0




		Uncoated

		8.5	0.3346"																	165	91.7	Round	8.5 mm	Standard	Dormer Pramet	3083A178	00000	—	———	0

Cobalt Steel Drill Bits


Jobbers' Length Round Shank	Short Length Round Shank	Split

Tough and wear resistant, cobalt steel bits last at least twice as long as high-speed steel. They can also run up to 25% faster at higher temperatures without being damaged on hard materials, such as nickel.

Jobbers' Length—These bits have the balance of rigidity and length needed for most applications.

Short Length—The most rigid bits for drilling the straightest holes.

Titanium Nitride (TiN) Coated—Drill at higher speeds and last longer than uncoated and oxide-coated bits, especially on tough materials like hardened steel and nickel.

Titanium Aluminum Nitride (TiAlN) Coated—The hardest and most wear-resistant coating, especially at high temperatures. These bits are best for hard and abrasive materials, such as iron, titanium, and fiberglass.

Uncoated—Polished to eject chips, these are also known as bright finish bits.

					Shank
	Drill Bit Size, mm	Decimal Size Equiv.	Overall Lg., mm	Max. Drilling Dp., mm	Type	Size	Drill Bit Point Type	Mfr.		Each
Jobbers' Length







				Titanium Nitride (TiN) Coated

				8.5	0.3346"	117	74.9	Round	8.5 mm	Split	Dormer Pramet	5058N72	000000




						Titanium Aluminum Nitride (TiAlN) Coated

						8.5	0.3346"	117	62.3	Round	8.5 mm	Split	Guhring	2753A177	00000




								Gold Oxide

								8.5	0.3346"	117	58	Round	8.5 mm	Split	Dormer Pramet	29355A138	00000


								Short Length







												Titanium Nitride (TiN) Coated

												8.5	0.3346"	79	20.1	Round	8.5 mm	Split	Chicago-Latrobe	2456N159	00000




														Uncoated

														8.5	0.3346"	79	20.1	Round	8.5 mm	Split	Chicago-Latrobe	2456N132	00000

Drill Bit Guides

Place these guides on your workpiece to drill precise holes without building a fixture. They'll even work on corners and round surfaces. Lines marked on the side allow you to align your holes accurately. Made of hardened steel, they’re tough enough to withstand frequent use.

For Drill Bit Size, mm	For Drill Bit Size Decimal Equiv.	Lg.	Wd.	Ht.	Material		Each
3, 3.3, 3.5, 4, 4.2, 4.5, 5, 5.5, 6, 6.5, 6.8, 7, 7.5, 8, 8.5, 9, 9.5	0.1181", 0.1299", 0.1378", 0.1575", 0.1654", 0.1772", 0.1968", 0.2165", 0.2362", 0.2559", 0.2677", 0.2756", 0.2953", 0.315", 0.3346", 0.3543", 0.374"	5 1/2"	3/4"	7/8"	Steel	9550T15	000000

Carbide Drill Bits

The hardest and most wear-resistant drill bits you can buy. Carbide bits stay sharp at high temperatures and faster speeds for the best performance on hard and difficult-to-machine materials. They last 10 to 20 times longer than their closest alternative, cobalt steel. Carbide can be brittle, however, so these bits require a rigid machine tool holder to prevent breakage and should not be used in hand drilling applications.

Jobbers' Length—These bits have the balance of rigidity and length needed for most applications.

Short Length—The most rigid bits for drilling the straightest holes.

Titanium Nitride (TiN) Coated—Drill at higher speeds and last longer than uncoated bits, especially on materials like hardened steel, iron, and stainless steel.

Titanium Aluminum Nitride (TiAlN) Coated—No drill bits last longer. These are the best for high-speed, high-temperature drilling of very hard and abrasive materials, including titanium and fiberglass.

Uncoated—Excellent for a range of materials but won't last as long as coated bits.

					Shank
	Drill Bit Size, mm	Decimal Size Equiv.	Overall Lg., mm	Max. Drilling Dp., mm	Type	Size	Drill Bit Point Type	Mfr.		Each
Jobbers' Length
Round Shank






				Uncoated

				8.5	0.3346"	101	63	Round	8.5 mm	Four Facet	Ultra Tool	3030A37	000000


				Short Length
				Round Shank






								Titanium Nitride (TiN) Coated

								8.5	0.3346"	70	32	Round	8.5 mm	Four Facet	Ultra Tool	27515A723	00000




										Titanium Aluminum Nitride (TiAlN) Coated

										8.5	0.3346"	70	32	Round	8.5 mm	Four Facet	Ultra Tool	8879A623	00000

Drill Bit Size Gauges

For

Metric

Measure drill bit sizes with these gauges.

For System of Measurement	For Use With	For Drill Bit Size, mm	Wd.	Ht.	Thk.	Material	Color	Mounting Hole Dia.		Each
Metric	Drills	1.5, 2.0, 2.25, 2.5, 2.75, 3.0, 3.25, 3.5, 3.75, 4.0, 4.25, 4.5, 4.75, 5.0, 5.25, 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.5, 9.0, 9.5, 10.0, 10.5, 11.0, 11.5, 12.0, 12.5	2 1/2"	6 1/2"	5/64"	Steel	Silver	1/8"	8986A64	000000

Carbide-Tipped Drill Bits

Jobbers' Length

Round Shank

Short Length

Round Shank

Extended Length

Round Shank


Standard	Split

Performance similar to solid carbide but at a lower price point. Like carbide bits, these are stronger than cobalt and high-speed steel and maintain their sharp edges when drilling abrasive material. However, when drilling tough metals like iron and hardened steel, upgrade to carbide for longer life.

Jobbers' Length—These bits have the balance of rigidity and length needed for most applications.

Short Length—The most rigid bits for drilling the straightest holes.

					Shank
	Drill Bit Size, mm	Decimal Size Equiv.	Overall Lg., mm	Max. Drilling Dp., mm	Type	Size	Drill Bit Point Type	Mfr.		Each
Jobbers' Length







				Uncoated

				8.5	0.3346"	121	71.1	Round	8.5 mm	Standard	Izar	28595A74	000000


				8.5	0.3346"	121	85	Round	8.5 mm	Split	ICS	28595A33	00000


				Short Length







								Uncoated

								8.5	0.3346"	76	25.5	Round	8.5 mm	Standard	Izar	28805A413	00000


								Extended Length







												Uncoated

												8.5	0.3346"	165	86	Round	8.5 mm	Standard	ICS	29465A117	00000

Coolant-Fed Carbide Drill Bits


Jobbers' Length Round Shank	Maintenance Length Round Shank

The hardest and most wear-resistant bits, these deliver coolant to reduce heat and evacuate chips. They are designed for CNC machines that supply coolant through the spindle rather than an external source, such as a hose and nozzle. Coolant flows directly from holes in the bit's tip onto the drilling surface. This speeds up cuts and leads to excellent performance in deep holes and tough materials such as stainless steel and titanium.

Jobbers' Length—These bits have the balance of rigidity and length needed for most applications.

Maintenance Length—Shorter than jobbers' length, these bits are more rigid for less wobble when drilling hard material. Also known as mechanics’ bits.

					Shank
	Drill Bit Size, mm	Decimal Size Equiv.	Overall Lg., mm	Max. Drilling Dp., mm	Type	Size	Drill Bit Point Type	Mfr.		Each
Jobbers' Length







				Titanium Aluminum Nitride (TiAlN) Coated

				8.5	0.3346"	102	61	Round	10 mm	Four Facet	Garr Tool	2396N342	0000000


				Maintenance Length







								Titanium Aluminum Nitride (TiAlN) Coated

								8.5	0.3346"	89	47	Round	10 mm	Four Facet	Garr Tool	2396N718	000000

Carbide Drill Bits for Carbon Fiber, Fiberglass, and Graphite

Jobbers' Length

Cut clean holes in abrasive material without fraying or delaminating the surface. Made of carbide, these bits resist wear to retain a sharp edge, even after after hundreds of cuts.

					Shank
	Drill Bit Size, mm	Decimal Size Equiv.	Overall Lg., mm	Max. Drilling Dp., mm	Type	Size, mm	Point Angle	Drill Bit Point Type	Bit Style	Mfr.		Each
Jobbers' Length







				Uncoated

				8.5	0.3346"	101	63	Round	8.5	140°	Brad	Fluted	Ultra Tool	2828A127	000000

Chip-Clearing Cobalt Steel Drill Bits


Jobbers' Length Parabolic Flute Round Shank	Split

Avoid clogs and dissipate heat with cobalt bits that last at least twice as long as high-speed steel. The flutes clear chips to improve coolant flow and prevent damage to the bit and the hole. They also speed up drilling since you don't have to stop to clear the bit manually.

Jobbers' Length—These bits have the balance of rigidity and length needed for most applications.

Uncoated—Polished to eject chips, these are also known as bright finish bits.

						Shank
	Drill Bit Size, mm	Decimal Size Equiv.	Overall Lg., mm	Max. Drilling Dp., mm	Flute Type	Type	Size, mm	Drill Bit Point Type	Mfr.		Each
Jobbers' Length







				Uncoated

				8.5	0.3346"	117	73	Parabolic	Round	8.5	Split	Viking Norseman Drill	2771N61	000000

Carbide-Tipped Drill Bits for Hardened Steel

Jobbers' Length

Round Shank

Straight flutes withstand the heavy pressure needed to penetrate hardened steel. These bits cut more aggressively and resist stress better than spiral-flute bits. A lower-priced alternative to solid carbide, they stay sharp when drilling abrasive material but won’t last as long.

Jobbers' Length—These bits have the balance of rigidity and length needed for most applications.

					Shank
	Drill Bit Size, mm	Decimal Size Equiv.	Overall Lg., mm	Max. Drilling Dp., mm	Type	Size	Drill Bit Point Type	Mfr.		Each
Jobbers' Length







				Uncoated

				8.5	0.3346"	121	34	Round	8.5 mm	Notched	Izar	2973A69	000000

Left-Hand Cobalt Steel Drill Bits

Jobbers' Length

Round Shank

Split

The flutes spiral in the opposite direction of other bits and stay sharp longer than high-speed steel. They’re primarily used to remove stripped screws. Choose a bit that’s slightly smaller than the diameter of the screw’s head. Set your power tool to rotate in reverse. Slowly drill in the center of the screw head, maintaining constant pressure. As the bit penetrates, it will catch onto the screw and reverse it out of the hole. If the screw is badly stripped, you might need to punch a starter hole. Also known as reverse-flute bits.

Jobbers' Length—These bits have the balance of rigidity and length needed for most applications.

Uncoated—Polished to eject chips, these are also known as bright finish bits.

					Shank					Each
	Drill Bit Size, mm	Decimal Size Equiv.	Overall Lg., mm	Max. Drilling Dp., mm	Type	Size	Drill Bit Point Type	Mfr.		1-4	5-Up
Jobbers' Length







				Uncoated

				8.5	0.3346"	121	87	Round	8.5 mm	Split	Viking Norseman Drill	3474A64	000000	000000

Chip-Clearing High-Speed Steel Drill Bits

Jobbers' Length

High Helix Flute

Round Shank

Jobbers' Length

Parabolic Flute

Round Shank

Split

With flutes that lift chips out of the hole, you don't have to stop drilling to clear these bits manually. They improve coolant flow to dissipate heat and prevent clogs that can damage the bit and ruin the hole. High-speed steel is good for general purpose drilling in most metals.

High Helix Flute—Less aggressive than parabolic flutes for cleaner cuts in soft metals.

Parabolic Flute—A U-shaped groove on the flutes cuts faster and clears chips more quickly than high-helix bits, so these are better for drilling deeper holes.

Jobbers' Length—These bits have the balance of rigidity and length needed for most applications.

Black Oxide—The dark finish increases wear resistance and reduces friction to improve chip flow, so these bits can last 50% longer than uncoated bits.

Titanium Nitride (TiN) Coated—Drill at higher speeds and last longer than uncoated and oxide-coated bits, especially on tough materials like hardened steel and nickel.

Uncoated—The most economical option, uncoated bits perform best when used on low-carbon steel and aluminum. Polished to reduce friction, they're also known as bright finish bits.

						Shank
	Drill Bit Size, mm	Decimal Size Equiv.	Overall Lg., mm	Max. Drilling Dp., mm	Flute Type	Type	Size, mm	Drill Bit Point Type	Mfr.		Each
Jobbers' Length







				Black Oxide

				8.5	0.3346"	117	58	High Helix	Round	8.5	Split	Dormer Pramet	30055A72	000000




						Titanium Nitride (TiN) Coated

						8.5	0.3346"	117	75	Parabolic	Round	8.5	Split	Dormer Pramet	7333N35	00000




								Uncoated

								8.5	0.3346"	117	58	Parabolic	Round	8.5	Split	Dormer Pramet	2754A37	00000

High-Speed Steel Drill Bits for Plastic

The precision-ground, 60° point penetrates gradually to prevent cracking and chipping. It also reduces heat that can deform the material. Use these bits for drilling into acrylic, laminate, and other plastics. They're made of wear-resistant high-speed steel.

Jobbers' Length About Jobbers' Length

					Shank
	Drill Bit Size, mm	Decimal Size Equiv.	Overall Lg., mm	Max. Drilling Dp., mm	Type	Size, mm	Point Angle	Drill Bit Point Type	Mfr.		Each
Uncoated



		8.5	0.3346"	117	86	Round	8.5	60°	Standard	ICS	27465A423	000000

Hex-Bit Taps

You only need one tool to turn these taps and install screws. The _1/4" hex shank fits hand or powered screwdrivers for threading holes. Then switch to a screwdriver bit to finish the job. To tap in hard-to-reach spots, add a bit extension. Taps have straight flutes that are good for most jobs.

High-Speed Steel—The most versatile taps resist heat and wear to stay sharp. They’re good for most metals and plastic.

Uncoated—The economical choice, these won't last as long as coated taps.

Plug Chamfer—Our go-to chamfer type, these thread both through holes and blind holes. The tapered section is shorter than a taper chamfer and longer than bottoming chamfer. As a result, they're easier to turn than bottoming taps but require more force than taper taps.

						Drill Bit				Plug Chamfer
	Thread Size	Thread Lg.	Overall Lg.	Thread Type	No. of Flutes	Size, mm	Decimal Size Equiv.	Shank Type	Hex Shank Size		Each
High-Speed Steel







				Uncoated

				M10 × 1.5 mm	13/16"	1 5/8"	Metric	4	8.5	0.3346"	Hex	1/4"	1021N31	000000

Quick-Change Hex Shank Drill Taps for Drills and Screwdrivers

Save time when you need to change drill taps frequently. The grooved shank snaps directly into drills, power screwdrivers, and other tools that accept a 1/4" hex shank. However, they’re not rated for impact drivers. With a drill bit point to drive into the workpiece, these taps can drill and tap holes in a single step. They’re made of high-speed steel and are for use on most metal and plastic.

Their spiral flutes keep chips clear by drawing them back toward the tap and out of the hole. All have a plug chamfer with 3-5 chamfered cutting threads, so they’re suitable for start-to-finish tapping.

Uncoated High-Speed Steel—Uncoated taps are strong enough for most tapping jobs but have the shortest tool life.

Titanium Nitride (TiN)-Coated High-Speed Steel—Titanium Nitride (TiN) coated taps resist heat and wear better than uncoated taps, letting them last up to twice as long.

	Thread			Drill Bit								Plug Chamfer
	Size	Lg.	Overall Lg.	Size, mm	Decimal Size Equiv.	Point Angle	Flute Type	No. of Flutes	Thread Type	Pitch Dia. Limit	Hex Shank Size		Each
Uncoated High-Speed Steel



		M10 × 1.5 mm	1 1/8"	3 15/16"	8.5	0.3346"	118°	Spiral	2	Metric	D6	1/4"	3464A56	000000


		Titanium Nitride (TiN)-Coated High-Speed Steel



				M10 × 1.5 mm	1 1/8"	3 15/16"	8.5	0.3346"	118°	Spiral	2	Metric	D6	1/4"	3464A132	00000

Depth-Limiting Drill Stops

Image of ProductInUse. Front orientation. Drill Stops.

Ensure identical hole depths every time. Position the collar on your bit and tighten the set screw.

	For Drill Bit Size Decimal Equiv.	Overall Lg.	OD	Hex Key Size for Set Screw	Material		Each
For Metric Drill Bits



	8.5 mm	0.3346"	3/4"	3/4"	3/32"	Steel	8865A206	00000

Drill Taps

Spiral Flute

Drill holes and cut threads without switching tools. Made of high-speed steel, these taps are for use on most metal and plastic. The square shank is compatible with tap holders for drill presses and milling machines. All have a plug chamfer with 3-5 chamfered cutting threads, so they're suitable for start-to-finish tapping.

Uncoated High-Speed Steel—Uncoated taps are strong enough for most tapping jobs but have the shortest tool life.

Spiral Flute—Taps with spiral flutes keep chips clear by drawing them back toward the tap and out of the hole.

	Thread			Drill Bit							Plug Chamfer
	Size	Lg.	Overall Lg.	Size, mm	Decimal Size Equiv.	Point Angle	Flute Type	No. of Flutes	Thread Type	Pitch Dia. Limit		Each
Uncoated High-Speed Steel



		M10 × 1.5 mm	1 1/16"	3 3/8"	8.5	0.3346"	110°	Spiral	2	Metric	D6	2748A67	000000

Left-Hand High-Speed Steel Drill Bits

Jobbers' Length

Round Shank

Standard

With flutes that spiral in the opposite direction of other bits, these are primarily used to remove stripped screws. Choose a bit that’s slightly smaller than the diameter of the screw’s head. Set your power tool to rotate in reverse. Slowly drill in the center of the screw head, maintaining constant pressure. As the bit penetrates, it will catch onto the screw and reverse it out of the hole. If the screw is badly stripped, you might need to punch a starter hole. Also known as reverse-flute bits. High-speed steel is the versatile choice for drilling most metals.

Jobbers' Length—These bits have the balance of rigidity and length needed for most applications.

Black Oxide—The dark finish increases wear resistance and reduces friction to improve chip flow, so these bits can last 50% longer than uncoated bits.

					Shank					Each
	Drill Bit Size, mm	Decimal Size Equiv.	Overall Lg., mm	Max. Drilling Dp., mm	Type	Size	Drill Bit Point Type	Mfr.		1-9	10-Up
Jobbers' Length







				Black Oxide

				8.5	0.3346"	117	63.9	Round	8.5 mm	Standard	Dormer Pramet	29855A68	000000	000000

Undersized Hardened Multipurpose M2 High-Speed Tool Steel Rods

These rods, also known as drill blanks, have an undersized diameter for machining your own drill bits. They're hardened for increased abrasion and impact resistance. M2 tool steel offers a nice balance of wear resistance and machinability. It has a high molybdenum content, which allows it to maintain sharp cutting edges even at elevated temperatures.

Certificates with a traceable lot number are available for these products. Download certificates from ORDER HISTORY after your order ships.

Dia., mm	Dia. Tolerance, mm	Drill Bit Size, mm	Lg.	Yield Strength	Hardness	Mechanical Finish		Each
8.5	-0.005 to 0	8.5	4 3/4"	Not Rated	Rockwell C60 (Extra Hard)	Precision Ground	2900A364	00000